Air Purifying Plants Keep Your Home's Air Quality Higher
Could air purifying plants improve your air quality in Shanghai?
As we spend most of our time indoors, it is important to make sure indoor air is clean.
Apart from outdoor pollution, other pollutants can affect indoor air quality, such as emissions from furniture and other building materials, gas from cooking, plastics and detergents etc.
If we close windows and doors to prevent outdoor pollution from
entering, or to save energy, it is even more critical to ensure indoor
air is purified.
The most expensive and effective way to clean indoor
air is to use air purifiers, but a cheaper method is
to use air purifying plants.
There are several plant and flower markets in Shanghai where you can find hundreds, if not thousands, of varieties of flowers and plants. These markets house many vendors under one roof, so you can usually get good prices just by doing comparison shopping, even if your bargaining skills aren't so great.
The vendors will arrange delivery, sometimes included for free depending on the amount of your purchase. In case you don't have a green thumb, there are also some vendors that will rent you plants, including a monthly maintenance service, to make sure they are watered correctly.
How do Plants Clean the Air?
Besides breathing in carbon dioxide and breathing out oxygen, air purifying plants also absorb other toxins.
There is some controversy about how effectively they do this, with the California Environmental Protection Agency stating in a 2005 report on Air Cleaning Devices for the home that "Houseplants do not effectively remove indoor air pollutants.
"One researcher has reported that certain air purifying plants can remove significant amounts of indoor air pollutants. However, six subsequent reviews, and a study in office buildings and portable office buildings, indicated that houseplants have very little, if any, effect on indoor pollutant levels.
"Small effects might occur, but only with an unreasonably large number of houseplants present, which could easily cause other indoor pollution problems such as excess moisture.” Read their full report here.
There have been, however, several studies that do show plants have many benefits, including purifying our indoor air.
The best-known study of air purifying plants was done by NASA and Dr. B.C. Wolverton in the 1970s and 80s. This study was carried out to find ways to clean air in orbiting space stations, where astronauts would be confined for long periods of time.
Dr. Wolverton went on to do many more of his own studies and published several books on the effectiveness of plants in purifying air.
The NASA study focused on 3 common toxins found in indoor air:
- Formaldehyde, which can be emitted by particle board or pressed wood products, used in manufacturing of office furniture, grocery bags, waxed papers, facial tissues and paper towels, adhesive binders in floor coverings, carpet backings and permanent-press clothes, heating and cooking fuels like natural gas, kerosene, and cigarette smoke.
- Benzene, which can be emitted by gasoline, inks, oils, paints, plastics, and rubber, detergents, pharmaceuticals, and dyes.
- Trichloroethylene, which can be emitted by printing inks, paints, lacquers, varnishes, and adhesives.
The results of the study showed that some air purifying plants can remove up to 87 percent of some air pollutants within 24 hours. Based on their studies, NASA recommended the use of 15 to 18 good-sized houseplants in a 170 m2 home or office.
Dr. B.C. Wolverton’s list of the 50 most effective air purifying plants, published in his book How to Grow Fresh Air, with rough translations into Chinese, can be found below.
A separate study from the Pennsylvania State University published in an issue of the American Society of Horticultural Science's journal HortTechnology revealed that three common houseplants; snake plant, spider plant, and golden pothos, all showed an ability to reduce ozone, another dangerous gas which Chinese authorities recently claimed was becoming a dangerous threat in Shanghai.
Air purifying plants are known to be very adaptable to their environment, as their air purifying capability increases over time. They learn to convert more of the toxic particles in their new environment into their own food source.
The NASA study also showed that the roots and exposed soil plays a big part in absorbing the toxins, so lower lying leaves and branches should be removed to ensure maximum contact with the air.
Some plants, however, can also be toxic, so you should check the list for safe plants if you have pets or young children.
Reducing Mold and Regulating Indoor Moisture
Another study published by Dr. Wolverton in 1996 in the Journal of the Mississippi Academy of Science showed that rooms with air purifying plants have 50 to 60 percent less airborne microbes, such as mold spores and bacteria, than similar rooms without plants.
Plants do this partly by reducing humidity levels indoors down to between 40 and 60 percent, the ideal level for humans, thereby helping to prevent mold growth.
Although some people recommend removing plants to reduce allergies, a reduction in mold spores and bacteria in the air could actually have a great benefit to allergy sufferers.
Another way air purifying plants reduce microbes is by releasing negative ions. In an article published in the Journal of Environmental Horticulture, also in 1996, Dr. Lohr, found that houseplants can reduce human stress and increase productivity by releasing negative ions, which have been known for many years to have health benefits to humans.
Ions can improve people’s mood, alleviate depression, and help to cure seasonal affective disorder (SAD, or winter depression).
Ions are charged particles in the air which can be produced by UV light, airflow friction, lighting, falling water and plants. As air purifying plants emit water vapors they produce negative ions. Many products found indoors such as plastics have a positive static charge that consumes large amounts of negative ions.
In another study (Atmospheric Environment, 1996, 30(14): 2565-2568) Dr. Lohr also showed that houseplants could reduce dust levels in a computer room by 20 percent, also helping allergy sufferers.
Can plants also make you work more effectively?
In a study published in 2011 in the Journal of Environmental Psychology, scientists showed that air purifying plants placed in an office helped to boost the attention span of office workers, showing that greenery has regenerative effects for directed attention.
There is a report extensively distributed around Chinese Social media sites promoting the effectiveness of 14 plants for their air purifying attributes. This report does not list who did the study, and just refers to ‘experts’.
Some of the same or similar plants can be found on the NASA list. You can find the list with a rough translation below.
Plants are not only beautiful, they can improve the air quality in your home
Caojiadu Flower and Bird Market in Shanghai
Flower and Plants Markets in Shanghai
Cao Jia Du Plant, Flower & Bird Market (The largest in Shanghai)
Add: 1148 Changshou Lu, near Wanhangdu Lu, Putuo District
Open till 18:00
Hongqiao Bird & Flower Market
Add: 718 Hongjing Lu, near Hongsong Lu,
虹桥花鸟市场地址: 上海闵行区718虹井路, 近红松路
Open till 18:00
Yongjia Flower Market
Add: 406 Shaanxi Nanlu, near Yongjia Lu
Open till 18:00
Pudong Flower Market
No. 620 Pujian Lu, near YangGao Nan Lu
Meiyuan Bird and Flower Market
49 Fushan Lu, Pudong New Area
Shanghai Metropolis Flower Market
Xizang Zhong Lu
behind Shanghai No 1 Department Store
Jingwen Flower Market
225 Shaanxi Nan Lu
Dr. B.C. Wolverton's List of 50 Plants and Rough Translations into Chinese
Dracaena "Janet Craig"
Dwarf Date Palm
Red Emerald Philodendron
Lacy Tree Philodendron
Elephant Ear Philodendron
Norfolk Island Pine
King of Hearts
Christmas and Easter Cactus
Chinese Evergreen "Silver Queen"
槟榔树Bīnláng shù 凤尾竹
女棕榈 棕竹Nǚ zōnglǘ Zōng zhú
竹棕榈Zhú zōnglǘ 棕竹
“珍妮特·克雷格” 龙血树 “zhēnnī tè·kè léi gé” Lóng xuè shù
英格兰常春藤Yīnggelan cháng chūnténg
海枣棕榈 hǎi zǎo Zōnglǘ
波士顿 蕨冷杉, 肾蕨 Bōshìdùn jué lěngshān, shèn jué
和平百合 白鹤 Hépíng bǎihé báihè
巴西木的 bāxī mù de
金伯利女王冷杉Jīnbólì nǚwáng lěngshān
花店妈妈菊花Huā diàn māmā júhuā
非洲菊 Fēizhōu jú
龙血树Lóng xuè shù
金边瑞香 龙血树jīnbiān ruìxiāng lóng xuè shù
红翡翠蔓蔓绿绒小红Hóng fěicuì màn màn lǜ róng xiǎo hóng
合果芋 Hé guǒ yù
甘蔗花叶万年青“珍品致密” Gānzhe huā yè wànniánqīng “zhēnpǐn zhìmì”
哭泣图叶榕Kūqì tú yèróng
五加科 鹅掌É zhǎng
蜡海棠 四季秋海棠 Là hǎitáng sìjì qiūhǎitáng
拉齐树 蔓绿绒 Lā qíshùmàn màn lǜ róng
心叶 蔓绿绒 Xīn yè màn lǜ róng
蛇植物 虎尾兰Shé zhíwù hǔwěi lán
象耳的蔓 蔓绿绒Xiàng ěr de màn màn lǜ róng
诺福克岛松南洋杉太子参Nuò fú kè dǎo sōng nányáng shān tàizǐ cān
红心国王千年健 Hóngxīn guówáng qiānnián jiàn
祈祷的植物马兰塔 Qídǎo de zhíwù mǎlán tǎ
矮蕉香蕉芭蕉Ǎi jiāo xiāngjiāo bājiāo
圣诞节和复活节仙人掌蟹爪兰 Shèngdàn jié hé fùhuó jié xiānrénzhǎng xiè zhuǎ lán
橡树叶常春藤白粉藤属 “埃伦达妮卡” Xiàngshù yè cháng chūnténg báifěn téng shǔ “āi lún dá nī kǎ”
百合山麦冬草Bǎihé shān mài dōngcǎo
兰花石斛石斛Lánhuā shíhú shíhú
中国长荣栽“银皇后” Zhōngguó zhǎng róng zāi “yín huánghòu”
巴豆变叶木 Bādòu biàn yèmù
矮杜鹃花 Ǎi dùjuān huā
孔雀竹芋植物Kǒngquè zhú yù zhíwù
仙客来Xiān kè lái
Chinese Report on the 14 Most Effective Air Purifying Plants
滴水观音：Dīshuǐ guānyīn Dripping Guanyin:
Can clear dust from air. However, it can be toxic, so make sure animals and children don't eat it.
君子兰: Jūnzǐlán Clivia (Gentleman orchid):
very effective in absorbing large amounts of air and releasing oxygen, even at night.
橡皮树: Xiàngpí shù Rubber tree:
Good for eliminating many harmful substances including carbon monoxide, carbon dioxide, hydrogen fluoride and other harmful gases as well as remove small particulate matter so reducing indoor dust.
文竹Wén zhú Asparagus ??:
The eradication of bacteria and virus protection umbrella. Asparagus's aroma has antibacterial ingredients, so can clear the air of bacteria and viruses. The roots are sometimes used as medicine.
银皇后： Yín huánghòu: Silver Queen (Chinese Evergreen):
Very suitable for dark rooms with poor ventilation.as it can clean air with high concentrations of pollutants.
铁线蕨：Tiě xiàn jué Adiantum (type of fern):
Good at absorbing formaldehyde (20 micrograms per hour). In addition, it can also inhibit the release of of xylene and toluene from computer monitors and printers.
吊兰: Diàolán: spider plants:
Effective in absorbing high amounts of carbon monoxide and formaldehyde under low lighting. Can also decompose benzene and nicotine from cigarette smoke. Known as the green indoor air purifier.
芦荟: Lúhuì: : Aloe:
Can absorb formaldehyde, carbon dioxide, sulfur dioxide, carbon monoxide and other harmful substances. Can kill harmful microorganisms in the air and can absorb dust. Spots will appear on Aloe leaves when the air is hazardous, so more plants should be added.
棕竹: Zōng zhú: Bamboo Palm:
Good at eliminating heavy metal pollution, carbon dioxide and sulfur dioxide. As a plant with large leaf foliage its biggest feature is ability to digest large amounts of carbon dioxide and produce oxygen.
龟背竹: Guī bèi zhú: Monstera:
Evergreen vines. Clears formaldehyde better than other plants, as well as is good at absorbing carbon dioxide and releasing oxygen during the night.
常春藤: Cháng chūnténg: Ivy:
The champion for absorbing formaldehyde. Ivy can also absorb benzene. Supposedly, 2-3 pots of Ivy in a 10 m2 room is enough to purify the air and adsorb small particulate dust.
富贵竹: Fùguì zhú: Lucky Bamboo:
Suitable for the bedroom. Effective in cleaning the air in rooms with poor ventilation. It also has a disinfectant function.
发财树: Fācái shù: Pachira:
Evergreen, through photosynthesis can absorb toxic gas and release oxygen. Effective in absorbing carbon monoxide and carbon dioxide, as well as smoke from tobacco.
仙人掌: Xiānrénzhǎng: Cactus:
Has a strong anti-inflammatory sterilization role in the fight against pollution. The cactus is the best plants to reduce electromagnetic radiation. In addition cactus absorb carbon dioxide and release oxygen at night so conducive for sleep.
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